
When driving on steep gradients, the
engine oil level must be sufficiently high to
ensure a correct oil supply in the vehicle.
XDEF tank (BlueTEC vehicles):check the
level and add if necessary (
Ypage 186).
XTire-changing tool kit: check that the jack
is working and make sure you have the lug
wrench, a robust tow cable and a folding
spade in the vehicle.
XWheels and tires: check the tire tread
depth and tire pressure.
XCheck for damage and remove any foreign
objects, e.g. small stones, from the
wheels/tires.
XReplace any missing valve caps.
XReplace dented or damaged wheels.
XRims: dented or bent rims can result in a
loss of tire pressure and damage the tire
bead. Before driving off-road, check the
wheels and replace them if necessary.
Checklist after driving off-road
!If you detect damage to the vehicle after
driving off-road, have the vehicle checked
immediately at a qualified specialist work-
shop.
Driving over rough terrain places greater
demands on your vehicle than driving on nor-
mal roads. After driving off-road, check the
vehicle. This allows you to detect damage
promptly and reduce the risk of an accident to
yourself and other road users.
XVehicles with the ON&OFFROAD pack-
age: activate the on-road program
(
Ypage 258).
XDeactivate the LOW RANGE off-road gear
(
Ypage 259).
XDeactivate DSR (Ypage 257).
XLower the vehicle level again to a level suit- able to the road conditions, e.g. to the high-
way level.
XClean the headlamps and rear lights and
check for damage.
XClean the front and rear license plates.
XClean the wheels and tires with a water jetand remove any foreign objects.
XClean the wheels, wheel housings and the
vehicle underside with a water jet; check
for any foreign objects and damage.
XCheck whether twigs or other parts of
plants have become trapped. These
increase the risk of fire and can damage
fuel pipes, brake hoses or the rubber bel-
lows of the axle joints and propeller shafts.
XAfter the trip, examine without fail the
entire undercarriage, wheels, tires, brakes,
bodywork structure, steering, chassis and
exhaust system for damage.
XAfter driving for extended periods across
sand, mud, gravel, water or in similarly dirty
conditions, have the brake discs, wheels,
brake pads/linings and axle joints checked
and cleaned.
XIf you detect strong vibrations after off-road travel, check for foreign objects in the
wheels and drive train and remove them if
necessary. Foreign objects can disturb the
balance and cause vibrations.
Driving on sand
Observe the following rules when driving on
sand:
RVehicles with the ON&OFFROAD pack-
age: select off-road program 1
(
Ypage 258).
RSelect a higher vehicle level.
RAvoid high engine speeds.
RUse the left-hand steering wheel paddle
shifter to shift to a lower gear appropriate
to the terrain.
200Driving tips
Driving and parking

Problems with PARKTRONIC
ProblemPossible causes/consequences andMSolutions
Only the red segments
in the PARKTRONIC
warning displays are lit.
You also hear a warning
tone for approximately
two seconds.
PARKTRONIC is deacti-
vated after approx-
imately five seconds,
and the indicator lamp
in the PARKTRONIC
button lights up.PARKTRONIC has malfunctioned and has switched off.
XIf problems persist, have PARKTRONIC checked at a qualified
specialist workshop.
Only the red segments
in the PARKTRONIC
warning displays are lit.
PARKTRONIC is deacti-
vated after approx-
imately five seconds.The PARKTRONIC sensors are dirty or there is interference.
XClean the PARKTRONIC sensors (Ypage 380).
XSwitch the ignition back on.
The problem may be caused by an external source of radio or
ultrasound waves.
XSee if PARKTRONIC functions in a different location.
Active Parking Assist
General notes
Active Parking Assist is an electronic parking
aid with ultrasound. It measures the road on
both sides of the vehicle. A parking symbol
indicates a suitable parking space. Active
steering intervention can assist you during
parking. You may also use PARKTRONIC
(
Ypage 224).
Important safety notes
Active Parking Assist is merely an aid. It is not
a replacement for your attention to your
immediate surroundings. You are always
responsible for safe maneuvering, parking
and exiting a parking space. Make sure that
no persons, animals or objects are in the
maneuvering range.
When PARKTRONIC is switched off, Active
Parking Assist is also unavailable.
GWARNING
While parking or pulling out of a parking
space, the vehicle swings out and can drive
onto areas of the oncoming lane. This could
result in a collision with another road user.
There is a risk of an accident.
Pay attention to other road users. Stop the
vehicle if necessary or cancel the Active Park- ing Assist parking procedure.
!If unavoidable, you should drive over
obstacles such as curbs slowly and not at a
sharp angle. Otherwise, you may damage
the wheels or tires.
Active Parking Assist may possibly indicate
parking spaces which are not suitable for
parking, for example:
Rwhere parking or stopping is prohibited
Rin front of driveways or entrances and exits
Ron unsuitable surfaces
Driving systems227
Driving and parking
Z

=Red guide linefor th evehicl ewidt hinclud -
in gth eexterio rmirrors, for curren tsteer -
in g whee langle (dynamic )
?Yellowlan emarking tires at curren tsteer -
in g whee langle (dynamic )
AYellowguide lin eat adistanc eof approx -
imately 3ft (1.0 m) from the rear of the
vehicle
BVehicle center axle (marker assistance)
CBumper
DRed guide line at a distance of approx-
imately 10 in (0.25 m) fromthe rear of the
vehicle
The guide lines are shown when the trans-
mission is in position R.
The distance specifications only apply to
objects that are at ground level.
Additional messages for vehicles with
PARKTRONIC
:
Front warning display
;Additional PARKTRONIC measurement
operational readiness indicator
=Rear warning display Vehicles with PARKTRONIC:
if
PARKTRONIC is operational (
Ypage 225), an
additional operational readiness indicator will
appear in COMAND display ;. If the
PARKTRONIC warning displays are active or
light up, warning displays :and =are also
active or light up correspondingly in the
COMAND display.
"Reverse parking" function
Backing up straight into a parking space
without turning the steering wheel
:White guide line without turning the steer-
ing wheel, vehicle width including the
exterior mirrors (static)
;Red guide line for the vehicle width includ-
ing the exterior mirrors, for current steer-
ing wheel angle (dynamic)
=Yellow guide line at a distance of approx-
imately 3 ft (1.0 m) fromthe rear of the
vehicle
?Red guide line at a distance of approx-
imately 10 in (0.25 m) fromthe rear of the
vehicle
Driving system s233
Driving an d parking
Z

XTo switch to full screen mode:select
Full Screen
by turning cVdthe
COMAND controller and press Wto con-
firm.
Displays in the COMAND display
Important safety notes
!Objects not at ground level may appear to
be further away than they actually are, e.g.:
Rthe bumper of a parked vehicle
Rthe drawbar of a trailer
Rthe ball coupling of a trailer tow hitch
Rthe rear section of an HGV
Ra slanted post
Use the guidelines only for orientation.
Approach objects no further than the bot-
tom-most guideline.
Top view with picture from the rear view
camera
:Symbol for the split screen setting with
top view and rear view camera image
;Yellow guide line at a distance of approx-
imately 13 ft (4.0 m) fromthe rear of the
vehicle
=Yellow guide line for the vehicle width
including the exterior mirrors, for current
steering wheel angle (dynamic)
?Yellow lane marking tires at current steer-
ing wheel angle (dynamic)
AYellow guide line at a distance of approx-
imately 3 ft (1.0 m) fromthe rear of the
vehicle
BVehicle center axle (marker assistance)
CRed guide line at a distance of approx-
imately 12 in (0.30 m) fromthe rear of the
vehicle
DBumper
The guide lines are shown when the trans-
mission is in position R.
The distance specifications only apply to
objects that are at ground level.
Top view with picture from the front cam- era
:Symbol for the split screen setting with
top view and front camera image
;Yellow guide line at a distance of approx-
imately 13 ft (4.0 m)from the front of the
vehicle
=Yellow guide line for the vehicle width
including the exterior mirrors, for current
steering wheel angle (dynamic)
?Yellow lane marking tires at current steer-
ing wheel angle (dynamic)
238Driving systems
Driving and parking

!A function or performance test should
only be carried out on a two-axle dyna-
mometer. Before you operate the vehicle
on such a dynamometer, please consult a
qualified workshop. You could otherwise
damage the drive train or the brake system.
iIn wintry driving conditions, the maximum
effect of 4MATIC can only be achieved if
you use winter tires (M+S tires), with snow
chains if necessary.
Further information about "Driving off-road"
(
Ypage 198).
DSR (Downhill Speed Regulation)
General notes
DSR is an aid to assist you when driving down-
hill. It keeps the speed of travel at the speed
selected on the on-board computer. The
steeper the downhill gradient, the greater the
DSR braking effect on the vehicle. When driv-
ing on flat stretches of road or on an uphill
gradient, the DSR braking effect is minimal or
nonexistent.
DSR controls the vehicle’s speed when it is
activated and the transmission is in position
D ,R or N. You can drive at a higher or a lower
speed than that set on the on-board computer
at any time by accelerating or braking.
Important safety notes
GWARNING
If the speed driven and the set speed deviate and you activate DSR on a slippery road sur-
face, the wheels may lose traction. There is an
increased danger of skidding and accidents.
Before switching DSR on, please take into
consideration the road surface and the differ- ence between driving speed and the set
speed.
If you fail to adapt your driving style, DSR can
neither reduce the risk of accident nor over-
ride the laws of physics. DSR cannot take
account of road, weather and traffic condi-
tions. DSR is only an aid. You are responsible for the distance to the vehicle in front, for
vehicle speed, for braking in good time and for
staying in your lane.
You are always responsible for keeping con-
trol of the vehicle and for assessing whether
the downhill gradient can be managed. DSR
may not always be able to keep to the set
speed, depending on road surface and tire
conditions. Select a set speed suitable for the
prevailing conditions and when necessary,
apply the brakes manually.
Activating DSR
XPress button
:.
Indicator lamp ;lights up.
The à DSR symbol appears in the mul-
tifunction display.
You can only activate DSR when driving at
speeds at or below 28 mph (40 km/h).
If the current vehicle speed is too high, the
à DSR symbol appears in the multifunc-
tion display with the Max. Speed 28 mph
message (Canada:40 km/h).
If you have activated DSR and you change the drive program, DSR is deactivated. If you
switch between the Offroad and Offroad Plus
drive programs, DSR remains activated.
Deactivating DSR
XPress button :.
Indicator lamp ;goes out.
The à DSR symbol appears in the mul-
tifunction display with the Off
message.
DSR switches off automatically if you drive
faster than 28 mph (Canada: 45 km/h). The
Driving systems257
Driving and parking
Z

using the brake controller and check
whether the brakes function correctly.
RSecure any objects on the trailer to prevent
the cargo from slipping when the vehicle is
in motion.
RWhen you couple up a trailer, check at reg-
ular intervals that the load isfirmly secured.
If the trailer isequipped with trailer lights
and brakes, check the trailer to ensure that
these are working.
RBear inmind that the handlin g will be less
stable when towing a trailer than when driv-
ing without one. Avoid sudden steering
movements.
RThe vehicle/trailer combination isheavier,
accelerates more slowly, has a decreased
gradient cli mbing capability and a longer
braking distance.
It is more susceptible to side winds and
requires more careful steering.
RIf possible, do not brake suddenly, but
instead depress the brake pedal moder-
ate lyat first so that the trailer can activate
it s brakes. Then increase the pressure on
the brake pedal.
RIf the automat ictransmission repeatedly
shifts between gears on uphill or downhill
gradients, shift to a lower gear using the
left-hand steering wheel paddleshifter.
A lower gear and lower speed reduce the
risk of engine failure.
RWhen drivingdown hill, shift to a lower gear
to uti lize the engine's braking effect.
Avoid co ntin
uous brake application as this
may overheat the vehicle brakes and, if
instal led,the trailer brakes.
RIfthe coolant temperature increases dra-
matical ly while the air-cond itioning system
is swit ched on, switch off the air-condition-
ing system.
Coolant heat can also bedissipated by
opening the windows and switching the ventilation
blower and the interior temper-
ature to the highest leve l.
RWhen overtaking, pay particular attention
to the extended length of your vehicle/
trailer combination.
Due to the length of the vehicle/trailer
combination, you require additional road
spaceinrelation to the vehicle you are
overtaking before you can change back to
the original lane.
Decoupling a trailer
GWARNIN G
If you uncouple atrailer wit hth eoverrun
brak eengaged ,you could trap your han d
between th evehicl eand th etrailer drawbar.
Ther eis aris kof injury.
Do no tuncouple atrailer if th eoverrun brak e
is engaged .
GWARNING
Vehicles wit hleve lcontrol :
The vehicl eis lowered as soo nas you discon -
nect th etrailer cable. This could result in your
limb sor those of other people that are
between th evehicl ebody and tires or under-
neath th evehicl ebein gtrapped .Ther eis a
ris kof injury.
Mak esure that nobody is in th eimmediat e
vicinity of th ewhee lhousing sor under th e
vehicl ewhen you disconnect th etrailer cable.
!Do not disconnect a trailer with an
engaged overrun brake. Otherwise, your
vehicle could bedamaged bythe rebound-
ing of the overrun brake.
XSh ift the transmission to position P.
XApply the vehicle's electr icparking brake.
XStart the engine.
XClose the doors and tailgate.
XApply the trailer's parking brake.
268Towing a trailer
Driving and parking

Tires
Display messagesPossible causes/consequences andMSolutions
Check Tire Pres‐
sure Soon
The tire pressure loss warning system has detected a significant
loss in pressure.
A warning tone also sounds.
Possible causes:
Ryou have changed the positions of the wheels and tires or instal-
led new wheels and tires.
Rthe tire pressure in one or more tires is not correct.
GWARNING
Tire pressures that are too low pose the following hazards:
Rthey may burst, especially as the load and vehicle speed
increase.
Rthey may wear excessively and/or unevenly, which may greatly
impair tire traction.
Rthe driving characteristics, as well as steering and braking, may
be greatly impaired.
There is a risk of an accident.
XStop the vehicle without making any sudden steering or braking
maneuvers. Pay attention to the traffic conditions as you do so.
XSecure the vehicle against rolling away (Ypage 189).
XCheck the tires and, if necessary, follow the instructions for a
flat tire (
Ypage 387).
XCheck the tire pressures and, if necessary, correct the tire pres-
sure.
XRestart the tire pressure loss warning system when the tire
pressure is correct (
Ypage 412).
Check Tire Pres‐
sure Then Restart
Run Flat Indicator
The tire pressure loss warning system generated a display mes-
sage and has not been restarted since.
XSet the correct tire pressure in all four tires.
XRestart the tire pressure loss warning system (Ypage 412).
RunFlatIndicator
Inoperative
The tire pressure loss warning system is faulty.
XVisit a qualified specialist workshop.
Please Correct
Tire Pressure
The tire pressure is too low in at least one of the tires, or the tire
pressure difference between the wheels is too great.
XCheck the tire pressures at the next opportunity (Ypage 412).
XIf necessary, correct the tire pressure.
XRestart the tire pressure monitor (Ypage 415).
318Displa y messages
On-board computer and displays

Display messagesPossible causes/consequences andMSolutions
Check TiresThe tire pressurein on eor mor etires has dropped significantly.
The whee lposition is displayed in th emultifunction display.
A warnin gtone also sounds.
GWARNIN G
Tirepressures that are to olow pos eth efollowing hazards :
Rthey may burst, especially as th eload and vehicl espeed
increase .
Rthey may wear excessivel yand/o runevenly, whic hmay greatl y
impair tire traction .
Rthedrivin gcharacteristics ,as well as steerin gand braking, may
be greatl yimpaired.
There is aris kof an accident.
XStop th evehicl ewithout makin gany sudden steerin gor brakin g
maneuvers .Pay attention to th etraffic condition sas you do so.
XSecur eth evehicl eagainst rollin gaway (Ypage 189).
XCheckth etires and ,if necessary, follow th einstruction sfo r a
flat tire (
Ypage 387).
XCheckth etire pressur e (Ypage 412).
XIf necessary, correc tth etire pressure.
Warnin gTir eMal ‐
function
The tire pressur ein on eor mor etires has dropped suddenly. The
whee lposition is shown in th emultifunction display.
GWARNIN G
Drivingwit h a flat tire poses aris kof th efollowing hazards :
Raflat tire affects th eabilit yto steer or brak eth evehicle.
Ryou could los econtrol of th evehicle.
Rcontinued drivin gwit h a flat tire will caus eexcessive heat build-
up and possibl y afire.
There is aris kof an accident.
XStop th evehicl ewithout makin gany sudden steerin gor brakin g
maneuvers .Pay attention to th etraffic condition sas you do so.
XSecur eth evehicl eagainst rollin gaway (Ypage 189).
XCheckth etires and ,if necessary, follow th einstruction sfo r a
flat tire (
Ypage 387).
Display messages319
On-board computer and displays
Z